Decay Constants of Pseudoscalar Mesons

TL;DR

This paper discusses how decay constants of pseudoscalar mesons are derived from decay rates, and uses these to predict other decay rates, including those for tau leptons, aligning well with experimental data.

Contribution

It introduces a method to estimate decay constants from dominant decay modes and applies these to predict less known decay rates, including tau-lepton decays.

Findings

Decay constants can be accurately estimated from dominant decay modes.

Predicted decay rates for less dominant modes match experimental measurements.

Decay rates for tau-lepton decays are successfully predicted.

Abstract

For purely leptonic decays of pseudoscalar mesons, the decay rates are related to the product of the relevant weak interaction-based CKM matrix element of the constituent quarks on the one hand, and the strong interaction parameter, the decay constant, which is related to the overlap of the quark and antiquark in the meson on the other hand. The decay constants for these mesons can thus be estimated from the decay rates of the respective dominant decay modes. The decay constants so obtained are used to estimate the decay rates of the less dominant modes, which are in good agreement with experimentally measured values. We also predict the decay rates for tau-lepton.